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Tag Archives: Typhoon Lan

Typhoon Lan brought wind and rain to parts of Japan on Sunday. At 5:00 p.m. EDT on Sunday the center of Typhoon Lan was located at latitude 35.2°N and longitude 139.1°E which put it about 50 miles southwest of Tokyo, Japan. Lan was moving toward the northeast at 37 m.p.h. (60 km/h). The maximum sustained wind speed was 80 m.p.h. (130 km/h) and there were wind gusts to 95 m.p.h. (155 km/h). The minimum surface pressure was 960 mb.

Typhoon Lan weakened significantly before it reached Japan. Lan moved over cooler water south of Japan. Strong upper level westerly winds caused strong vertical wind shear. The circulation of Lan pulled drier air into the western half of the circulation. The combination of cooler water, strong shear and drier air caused the significant weakening. In addition the shear was strong enough to push the heavier rain to the northeast of the center of Typhoon Lan.

Lan was still a typhoon when it made landfall in Honshu despite the unfavorable environment. A weather station at the Tokyo International Airport reported a wind speed of 56 m.p.h. (90 km/h). Some areas in eastern Honshu experienced periods of heavy rain and gusty winds. The drier air will limit the rainfall after the center of the typhoon passes a given location.

The strong westerly winds will steer Typhoon Lan rapidly toward the northeast. Lan will move east of Honshu in a few hours. The strong vertical wind shear and cooler, drier air will cause Typhoon Lan to transition to a strong extratropical cyclone east of Japan.

While Typhoon Lan races across eastern Japan, Tropical Depression 27W organized southeast of Guam. At 5:00 p.m. EDT on Sunday the center of Tropical Depression 27W was located at latitude 9.3°N and longitude 147.4°E which put it about 360 miles (580 km) southeast of Guam. It was moving toward west at 8 m.p.h. (13 km/h). The maximum sustained wind speed was 35 m.p.h. (55 km/h) and there were wind gust to 45 m.p.h. The minimum surface pressure was 1004 mb.

Tropical Depression 27W will move through an environment that will be somewhat favorable for development during the next several days. It will move over water where the Sea Surface Temperature is near 30°C. An upper level ridge centered northeast of the Marianas is producing easterly winds which are blowing over the top of the depression. Those winds are causing moderate vertical wind shear. The shear is inhibiting the organization of the circulation and it is slowing the development of the depression. The shear is forecast to decrease during the next several days and the depression could strengthen into a tropical storm if a distinct low level center forms.

Tropical Depression 27W is near the southwestern end of the ridge to its northeast. The ridge is currently steering the depression toward the west. It is forecast to move around the end of the ridge and turn more toward the north during the next few days. On its anticipated track the depression could be near Guam in about 24 hours. It could be a tropical storm at that time.

Powerful Typhoon Lan sped toward Japan on Saturday. At 11:00 p.m. EDT on Saturday the center of Typhoon Lan was located at latitude 28.9°N and longitude 134.5°E, which put it about 575 miles (925 km) southwest of Tokyo, Japan. Lan was moving toward the north-northeast at 27 m.p.h. (43 km/h). The maximum sustained wind speed was 145 m.p.h. (230 km/h) and there were wind gusts to 170 m.p.h. (275 km/h). The minimum surface pressure was 928 mb.

Lan is a large and powerful typhoon. There is an eye at the center of circulation, but the eye has become less clear during the past few hours. A ring of strong thunderstorms surrounds the eye and the strongest winds are occurring in that ring of storms. Additional bands of showers and thunderstorms are revolving around the core of Typhoon Lan. The outer bands in the western half of the circulation consist primarily of low clouds and showers. Winds to typhoon force extend out about 45 miles (75 km) from the center of circulation. Winds to tropical storm force extend out about 335 miles (540 km) from the center.

Typhoon Lan has reached its maximum intensity and it will weaken during the next several days. Lan is moving over water where the Sea Surface Temperature is near 28°C, but it will move over colder water when it moves farther north. Westerly winds in the upper levels are starting to increase the vertical wind shear. Typhoon Lan also appears to be drawing cooler and drier air into the western side of the circulation. Cooler water, more vertical wind shear and drier air will cause steady weakening of Typhoon Lan.

Typhoon Lan is moving around the western end of a ridge which is steering the typhoon rapidly toward the north-northeast. Westerly winds in the upper levels will carry Lan quickly toward Japan. On its anticipated track Typhoon Lan will approach Honshu and the area near Tokyo in 12 to 18 hours. Lan will still be a strong typhoon when it gets to Japan. Typhoon will bring strong winds and drop locally heavy rain over the area around Tokyo. Heavy rain could cause flash floods.

Typhoon Lan intensified into the equivalent of a major hurricane on Friday. At 11:00 a.m. EDT on Friday the center of Typhoon Lan was located at latitude 20.9°N and longitude 130.3°E which put it about 450 miles (720 km) south-southeast of Okinawa. Lan was moving toward the north at 8 m.p.h. (13 km/h). The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 145 m.p.h. (230 km/h). The minimum surface pressure was 942 mb.

Typhoon Lan has a large and powerful circulation. There is a large circular eye at the center of circulation. The eye has a diameter of 60 miles (96 km) and it is surrounded by a ring of strong thunderstorms. The strongest winds are occurring in that ring of storms. Multiple bands of showers and thunderstorms are revolving around the core of the circulation. Typhoon Lan is generating strong upper level divergence which is pumping mass away to the northeast of the typhoon. Winds to typhoon force extend out about 100 miles (160 km) from the center of circulation. Winds to tropical storm force extend out about 330 miles (530 km) from the center.

The Hurricane Intensity Index (HII) for Typhoon Lan is 20.6. The Hurricane Size Index (HSI) is 37.2 and the Hurricane Wind Intensity Size Index (HWISI) is 57.8. Those indices indicate that Typhoon Lan is capable of causing widespread major damage.

Typhoon Lan will move through an environment that will be favorable for further intensification during the next 24 hours. Lan will move over water where the Sea Surface Temperature is near 31°C. An upper level ridge centered east of Lan is producing southerly winds which are blowing toward the top of the circulation. There are also southerly winds in the lower levels of the atmosphere and thus there is not much vertical wind shear. The southerly winds in the upper levels are actually enhancing the upper level divergence to the northeast of Typhoon Lan. Warm water and little vertical wind shear will allow Typhoon Lan to strengthen during the next day or so. When Lan moves farther north, it will reach the upper level westerly winds in the middle latitudes. The vertical wind shear will increase at that time, and Typhoon Lan will start to weaken.

Typhoon Lan is moving around the western end of a subtropical ridge which is steering the typhoon toward the north. As Typhoon Lan moves farther toward the north, it will begin to move toward the north-northeast. When Lan reaches the upper level westerlies on Sunday, it will turn more toward the northeast. On its anticipated track the center of Typhoon Lan will pass east of Okinawa and the Ryuku Islands on Saturday. Typhoon Lan will approach Honshu in about 48 hours.

Typhoon Lan will still be a large powerful typhoon when it approaches Honshu. Lan will be capable of producing strong gusty winds and very heavy rainfall. Flash floods could occur when Typhoon Lan moves across Japan.

Typhoon Lan headed northward and strengthened on Thursday. At 11:00 p.m. EDT on Thursday the center of Typhoon Lan was located at latitude 19.2°N and longitude 130.0°E which put it about 550 miles (885 km) south-southeast of Okinawa. Lan was moving toward the north at 10 m.p.h. (16 km/h). The maximum sustained wind speed was 100 m.p.h. (160 km/h) and there were wind gusts to 125 m.p.h. (200 km/h). The minimum surface pressure was 956 mb.

Lan strengthened into a large powerful typhoon on Thursday. A big circular eye developed at the core of Typhoon Lan. The eye was not perfectly clear. There was a small area of convection at the center of the eye and there was a clear moat around that area. A ring of thunderstorms surrounded the eye and the strongest winds were occurring in that ring of storms. Multiple bands of showers and thunderstorms were revolving around the typhoon. Lan is a very large typhoon. Winds to typhoon force extended out up to 140 miles (225 km) from the center of circulation. Winds to tropical storm force extended out up to 305 miles (490 km) from the center

The Hurricane Intensity Index (HII) for Typhoon Lan was 16.5. The Hurricane Size Index (HSI) was 46.8 and the Hurricane Wind Intensity Size Index (HWISI) was 63.3. The circulation of Typhoon Lan is almost as large as the circulation of Hurricane Sandy was when Sandy hit the U.S. in 2012.

Typhoon Lan will be moving through an environment favorable for further intensification. Lan will move over water where the Sea Surface Temperature is near 30°C. It will move through and area where the upper level winds are weak and there will be little vertical wind shear. Typhoon Lan could intensify into the equivalent of a major hurricane during the next day or two.

Typhoon Lan is moving around the western end of a subtropical ridge which is steering the typhoon toward the north. Lan is likely to continue to move toward the north on Friday. The typhoon will be affected by westerly winds when it moves farther north. Those winds will cause Typhoon Lan to move more toward the north-northeast during the weekend. On its anticipated track the center of Typhoon Lan could pass southeast of Okinawa in 24 to 36 hours. Lan could approach Honshu within three days.

Tropical Storm Lan strengthened east of the Philippines on Tuesday and the Japan Meteorological Agency designated it a typhoon. At 5:00 p.m. EDT on Tuesday the center of Typhoon Lan was located at latitude 11.2°N and longitude 132.4°E which put it about 515 miles (830 km) east of the Philippines. Lan was moving toward the north-northeast at 5 m.p.h. (8 km/h). The maximum sustained wind speed was 75 m.p.h. (120 km/h) and there were wind gusts to 90 m.p.h. (150 km/h). The minimum surface pressure was 976 mb.

The circulation of Typhoon Lan became much more well organized on Tuesday. Several long rainbands developed in the circulation and other smaller bands formed in the periphery of the typhoon. The circulation of Typhoon Lan was circular and symmetrical. Thunderstorms near the core of Lan began to generate strong upper level divergence which was pumping mass away from the typhoon in all directions. The upper level divergence allowed the surface pressure to decrease and the wind speed to increase. Lan is a large typhoon. Winds to tropical storm force extend out about 230 miles (370 km) from the center of circulation.

Typhoon Lan will move through an environment favorable for intensification. Lan will move over water where the Sea Surface Temperature is near 30°C. Typhoon Lan will move through an area where the upper level winds will be weak and there will be little vertical wind shear during the next several days. Typhoon Lan will continue to strengthen and there could be a period of rapid intensification after a well formed eye develops at the center of circulation.

Typhoon Lan was in an area where the steering currents were weak and it moved little on Tuesday. An upper level ridge north of Lan blocked the typhoon from moving northward. A weakness is forecast to develop in the ridge and the models are forecasting that Typhoon Lan will move northward during the rest of this week. On its anticipated track Typhoon Lan will remain east of the Philippines. Lan could be southeast of Okinawa in three or four days.